Acute myocardial infarction (AMI) is the result of interruption of blood supply to a part of the heart, causing heart cells to die. During AMI, damage is caused to the cardiac tissue by prolonged ischemia as well as due to injury during reperfusion.
Neurohormonal modulation, including inhibition of the sympathetic tone and activation of the parasympathetic tone to the heart, has been shown to have a protective effect on the cardiac tissue during ischemia and during reperfusion of the heart.
Beta blockers which inhibit the beta sympathetic tone are typically used in the treatment of AMI. There is evidence that intravenous beta blockers, administered acutely to treat AMI, reduce in-hospital mortality resulting from myocardial infarction, and are also useful in the control of the pain associated with AMI. Acute intravenous administration of beta blockers has been shown to improve the myocardial oxygen supply-demand relationship, decrease pain, reduce infarct size, and decrease the incidence of serious ventricular arrhythmias.
Typically, percutaneous coronary interventions are used to treat AMI. For example, procedures such as balloon dilatation and stent implantatibn are used to open a stenosis in the coronary arteries so as to re-perfuse the heart.
Reperfusion therapy is typically used in the treatment of ST elevation myocardial infarction (STEMI). Primary percutaneous coronary intervention (PCI) typically improves survival of STEMI. Ischemia and/or reperfusion injury is still an unresolved problem in STEMI treated by reperfusion therapy. Primary PCI can restore epicardial flow in 90-95% of patients, but 15-20% of patients do not achieve microvascular flow (known as the “no flow” phenomenon). Lack of microvascular perfusion after STEMI is the primary determinant of LV remodeling.
Heart failure is a condition in which a problem with the structure or function of the heart impairs its ability to supply sufficient blood flow to meet the body's needs. The condition impairs quality of life and is a leading cause of hospitalizations and mortality in the western world. Treatment of heart failure is typically aimed at removal of precipitating causes, prevention of deterioration in cardiac function, and control of congestive state.
Hypertension, or chronic high blood pressure, is an extremely prevalent medical condition, which can lead to strokes, heart attacks, and heart failure. There are a variety of treatments that are available for treating hypertension, including lifestyle changes, and medication.